From owner-freebsd-fs@FreeBSD.ORG Mon May 20 15:01:49 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 57843786 for ; Mon, 20 May 2013 15:01:49 +0000 (UTC) (envelope-from josh@signalboxes.net) Received: from mail-ob0-x22c.google.com (mail-ob0-x22c.google.com [IPv6:2607:f8b0:4003:c01::22c]) by mx1.freebsd.org (Postfix) with ESMTP id 2304BF3A for ; Mon, 20 May 2013 15:01:48 +0000 (UTC) Received: by mail-ob0-f172.google.com with SMTP id tb18so7169072obb.17 for ; Mon, 20 May 2013 08:01:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:mime-version:x-received:date:message-id:subject:from:to :content-type:x-gm-message-state; bh=SvsaEs/X0rUnTm/422Xqnkt9jH+8U8MWuYNkT3aSFts=; b=hGclZoL0DiBt1Z3QqBSqHGEVMW0dmTL1tnQ5LHiNq+0rJZ4+e3ZbItjqHJsf3NdJFT MlXCVlPFOXAg9LLupjTB9ccRPwiVEpGZkBAffpZkTCSXbP9QcYuORdSKJ8KsHTb+XLln ByBBt/eF8hmohTeq7dVLU96y+bWj3Ui1rSgYX/bD9BI607GfB2LzN2ACgbDDnxjYOuwf jBmuOmcs6tKbPnVtAiCmpHq2wnJJYlwao38dKwxi2cc/3txkW11MzSzGtfaEXxvhhklR FJ1YBH5IW6KeBOuKC1eFl4hJWMx6aTu8vyFbGLGJh5ARFMLywS61ETHVGZ4+1P2LGYI6 d6YA== X-Received: by 10.60.83.49 with SMTP id n17mr941116oey.80.1369061617022; Mon, 20 May 2013 07:53:37 -0700 (PDT) Received: from mail-oa0-f43.google.com (mail-oa0-f43.google.com [209.85.219.43]) by mx.google.com with ESMTPSA id ns4sm20498252obc.2.2013.05.20.07.53.36 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 20 May 2013 07:53:36 -0700 (PDT) Received: by mail-oa0-f43.google.com with SMTP id o6so7754484oag.2 for ; Mon, 20 May 2013 07:53:36 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.60.125.232 with SMTP id mt8mr23627038oeb.33.1369061616294; Mon, 20 May 2013 07:53:36 -0700 (PDT) Received: by 10.60.79.194 with HTTP; Mon, 20 May 2013 07:53:36 -0700 (PDT) Date: Mon, 20 May 2013 08:53:36 -0600 Message-ID: Subject: L2ARC and ZIL on same SSD? From: Josh Beard To: freebsd-fs@freebsd.org X-Gm-Message-State: ALoCoQmlKhL3SiJXKbtyO4OLTYCfAntbWt4crxuiQje1piLqUMQjG84suaJh9NxHx+51aLrTakvv Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 May 2013 15:01:49 -0000 Hello, I have a file server running 9.1-RELEASE with 24 GB of RAM and a 6 TB zpool spread across 12 500GB disks in two raidz1 and 2 spares. This server houses hundreds of home directories for end-users and stays pretty busy with both read and writes. I'm planning to add two SSDs soon (128 GB each) to help performance and was planning to mirror them. I was curious if having the L2ARC and ZIL on the same disks (mirrored) is okay. With some searching, I haven't seen any "official" word on this. I've seen some folks say not to and others recommend it. Adding a second set of SSDs isn't desirable, as I'll start cutting into my available storage capacity (16 bay system). Any advice or experience with this? Thanks, Josh